The present invention is related to the field of semiconductor processing and, more particularly, to the design of semiconductor bath systems used in cleaning and rinsing semiconductor wafers.
Semiconductor bath systems clean and rinse semiconductor wafers. Often corrosive fluids, such as various acids, are used in the bath system. To protect the bath system's tank, which holds the fluids, and the different elements which are mounted to the tank, a housing encloses the sides of the tank.
However, despite the fact that the joint between the tank and housing is usually sealed, a recurring problem is that the seal between the tank and housing is often broken. The constant dripping of corrosive fluids and the condensation of such corrosive fumes generated by the semiconductor processes eventually cause the seal to lose its integrity. With the breach of the seal, it is a short time before the elements and connections to the tank are adversely affected by leaking fluids and the bath system is rendered inoperative. The failure typically requires removal of the bath system from a so-called "wet bench" in the semiconductor fabrication facility and a disassembly of the bath system to effect a repair. The failure is inconvenient, expensive and may affect production efficiencies of the facility.
One solution to this problem has been to keep the seal at the tank-housing joint in a pool of water so that corrosive fluids are washed away. However, this solution is cumbersome because a trough of water must be inconveniently maintained high against the outside walls of the tank and housing where they are joined and sealed. On the other hand, the present invention provides for the washing of the joint and seal in an arrangement which is compatible and convenient with present semiconductor processing systems.